MPs in both Conservative and Labour parties are yearning for a leader who will
show courage and imagination

British Obamas are like buses. As the cliché has it, you wait ages for one, and then two arrive at once. Adam Afriyie, the multi-millionaire MP for Windsor, has been touted as a surprise potential challenger to David Cameron while Chuka Umunna, the shadow business secretary widely tipped as a future leader, is routinely labelled a Barack for Brits.

The two men have much in common. Both are suave performers, both have mixed heritage, and both have known some hardship. Mr Afriyie’s Ghanaian father was largely absent during his childhood, and Mr Umunna’s dad washed cars for a living after arriving penniless from Nigeria.

Reports that Mr Afriyie has become the figurehead for Tory malcontents intent on destroying Mr Cameron have prompted him to proclaim himself “100 per cent” behind the leader. Despite being singled out by some senior Labour figures as an heir apparent, and introduced to Tony Blair on that presumption, Mr Umunna will continue to be unimpeachably – and genuinely – loyal to his “mate”, Ed Miliband.

Mr Afriyie will, most probably, never lead his party, while Mr Umunna may have to defer to other talented newcomers, such as Rachel Reeves or Liz Kendall. On the great bus route of politics, the Afriyie bandwagon has crashed into the buffers while the Umunna model remains mothballed in the showroom. Even so, the British Obamas, and Mr Afriyie in particular, offer a reminder of the ephemeral nature of power. Labour frontbenchers, led into the last election by Gordon Brown, a leader already exceeding his political shelf-life when he became PM, tend to view seven years as the watershed between accession and decline.

Thus they scrutinise Mr Cameron, who has now led his party for that timespan, as a householder might regard a mouldering pot of rhubarb yoghurt. Is he past his use-by date? Tory dissenters with little doubt that their leader’s time is up have cause to fear for their own survival after yesterday’s portentous vote in which the Tory plan for boundary changes was defeated, as expected, with the Lib Dems voting for the first time in the Commons against their Coalition partners in a move likely to cost the Tories around 20 seats.

That impending threat, plus the fury over gay marriage, drove Mr Cameron to offer an in/out EU referendum designed to pacify Tory rebels and discomfit Ed Miliband. It worked. Labour’s initial response was muddled, and the leader’s closest allies expected a four-point drop in the polls. Despite relief at an immediate dip of only two or three points, several shadow cabinet members remain uneasy about Labour’s stance on Europe. Outside the party, some wonder just how secure Mr Miliband really is.

For now, however, the pressure is all on Mr Cameron. The emergence of the Tory Obama is not principally a sign that leadership is transitory or that the Tories may not ever win another outright majority unless they can attract the ethnic vote and shed their posh boy image. The desire for a different sort of leader reflects the hunger, common to irate back-benchers and to ordinary voters, for the inspirational change promised by the first-term Obama and delivered by his predecessor and enabler, Abraham Lincoln.

With exceptions such as Mr Miliband, who has yet to see it, British politicians extol the Lincoln biopic. Douglas Alexander, the shadow foreign secretary, drew the sharpest conclusion in his Chatham House speech on Europe. Whereas Lincoln, in passing a 13th amendment to abolish slavery, “was willing to contemplate low politics to try and achieve historic change”, Mr Cameron, in offering his referendum, was “willing to contemplate historic change to try and achieve low politics”.

The comparisons do not end there. With a triple-dip recession looming and an electorate desperate to see courage and imagination, we have a Prime Minister who thinks small but shows belated signs of acting big, at least on Europe and high-speed rail. The Leader of the Opposition, conversely, thinks big, with majestic schemes to rebuild capitalism and forge one-nation Britain, but acts small, restricting himself to bite-sized policy morsels, such as cracking down on unscrupulous landlords.

Anyone who is expecting Ed Lincoln to surface, at least this side of party conference, is in for a disappointment. Labour sees no need to reveal fully fledged policies, especially since a fixed-term Parliament removes any necessity for an early manifesto. Yet some Labour insiders are anxious. Mr Miliband, they say, is bearing too much of the burden of renaissance while his shadow cabinet – with some notable exceptions, Ed Balls included – is unwilling, or unable, to do its share.

Senior figures remain bullish, arguing (almost certainly correctly) that the PM’s EU bluster will come back to haunt him. Mr Miliband’s thinking, one influential insider claims, cannot be compared to Mr Cameron’s “dead parrot project” of modernisation, now reduced to “jangling incoherence”. As Ed allies add, voters care most about the economy, on which George Osborne looks trapped in a purgatory of his own making.

Yet Labour cannot rely on surfing home on Treasury bungling and Coalition gridlock. The Tories’ commendable decision to pick up the plan developed by Labour’s Andrew Adonis for HS2 and their unveiling of a child care policy, substandard as it is, suggest that Mr Cameron retains the potential to wrongfoot Labour.

Gavin Kelly, once a senior aide to Gordon Brown, wrote this week about the possibility that the Tories could promise to restore the 10p income tax band abolished by Mr Brown. Remote as that prospect may be, even the possibility that the Tories could outflank Labour on such a totemic issue should petrify the opposition.

Europe aside, Mr Cameron is happy to take on internal enemies. So is Mr Osborne, whose taste for fast trains and fracking is persuading some Tories that he plans to turn his constituency of Tatton into a blighted Timbuktu.

Mr Miliband, by contrast, deserves a Nobel peace prize for defanging Labour’s warring factions. But unity, however desirable to a party of instinctive pitbulls, comes at a price. There is, for example, a tension, reflected in the relative silence on issues such as crime and rehabilitation, between Labour’s authoritarian and liberal wings. Personal rivalries have been subdued but not expunged, and backbench nerves persist. Sooner or later, Mr Miliband will have to face some fights or risk the chloroform effect of too much political tranquilliser.

This week’s slight narrowing of the polls should be a reminder of what awaits either leader, should he slip below the magic 30 points. At that margin, as Mr Brown found out, edgy backbenchers grow ungovernable, and ungovernable ones become regicidal.

Labour Party squeamishness, a lack of willing assassins and the fact that Mr Miliband attracts much more respect than doubt means he is more likely to be abducted by Martians than to be replaced this side of the election. None the less, the onus is on Labour to gloat a little less about Tory deficiencies and to worry a little more about its own. Like Lincoln, Mr Miliband must convince voters that his would truly be a government “of the people, by the people, for the people”.

If he cannot do so, then Mr Cameron – who commands neither the confidence of the people nor the affection of his party – may yet prove the more durable.